Abstract

We report broadband visible photoluminescence from solid graphene oxide, and modifications of the emission spectrum by progressive chemical reduction. The data suggest a gapping of the two-dimensional electronic system by removal of -electrons. We discuss possible gapping mechanisms, and propose that a Kekule pattern of bond distortions may account for the observed behavior.

Received 21 January 2009Accepted 21 February 2009Published online 19 March 2009

Acknowledgments:

P.V. and J.K. supported by NSF MRSEC under Grant No. DMR05–20020, Z.L. and A.J. supported by the JSTO DTRA and ARO under Grant No. W911NF-06–1-0462, and E.M. supported by DOE under Grant No. DE-FG02-ER45118.